Several large-scale epidemiologic investigations have uncovered relationships between chronic periodontal disease and adverse cardiovascular outcomes such as coronary heart disease and stroke. To date, endodontic inflammation has not received the same attention despite its being a commonly found sequel to bacterial infection of the Dental pulp space and its having several important characteristics in common with inflammation of periodontal origin. These similarities form the basis of the proposed epidemiologic study, which seeks to test the hypothesis that a greater history of endodontic inflammation is associated with 1) increased risk of coronary heart disease and stroke; and 2) increased carotid artery intimal-medial thickness and prevalence of coronary heart disease. These hypotheses will be addressed by linking data from three large, well-established, ongoing epidemiologic studies of aging populations with newly collected variables involving endodontic disease and treatment. Two of the three sub-studies (from populations of adult men in Boston and adult women in Sweden) will employ a review of existing intra- and extra-oral radiographs to assess variables related to apical periodontitis and frequency and quality of root canal therapy, and will relate these exposures to subsequent incidence of coronary heart disease and stroke. The third sub-study (from adult populations in four U.S. communities) will compare self-reports of endodontic treatment with prevalence of coronary heart disease and thickened carotid arterial walls in a cross-sectional fashion. Given the relatively high frequency of endodontic inflammation among adult populations, the proposed study describes a straightforward, fast, and inexpensive way to gain preliminary insight into the relationship between endodontic and cardiovascular disease. It also will serve as the epidemiologic foundation for future investigations into endodontic disease and other systemic outcomes.